1) Lightly grease a large frying pan and fry onion and red pepper on medium heat until just browned. Add kidney beans and mash into a paste with potato masher or a fork. Stir often. Crumble tofu and add to pan.
2) Heat mixture until bubbling. Add taco seasoning and mix thoroughly. Allow to cook for just a couple of minutes to allow tofu to absorb flavors.
3) Spoon mixture into taco shells, filling about halfway. Add toppings to your liking.
Source of recipe: I came up with this recipe while experimenting in the kitchen.